It is known in the art to reinforce high-performance concretes by means of steel fibers.
BE-A3-1005815 (N.V. BEKAERT S.A.) teaches that for conventional concretes with a compressive strength ranging from 30 MPa to 50 MPa, it makes no sense to increase the tensile strength of a steel fiber above 1300 MPa since an increase in tensile strength does not add any increase in flexural strength to the reinforced concrete. BE 1005815 further teaches, however, that for concretes with an increased compressive strength, the tensile strength of the steel fibers should increase proportionally.
WO-A1-95/01316 (BOUYGUES) adapts the average length of metal fibers to the maximum size of granular elements which are present in high-performance concrete so that metal fibers act as conventional rebars in high-performance concrete. The volume percentage of metal fibers in high-performance concrete is relatively high and ranges
DE-A1-33 47 675 (LAMPRECHT Gerd) relates to an artificial stone of cement or gypsum reinforced by means of thin fibers made of a high-alloyed steel. The high-alloyed steel fibers are provided with roughnesses on their surface in order to increase the adhesion in the cement and the gypsum. The fibers have a diameter ranging from 0.05 mm to 0.15 mm and the depth of the roughnesses is limited to 30% of the diameter of the fibers.